[CIFS] Add support for legacy servers part 5

Handle small negotiated read sizes (under 4K) and finish up
read and write support.

Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 0485c6d6ecd5..0fbe02ebc033 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -169,6 +169,10 @@ int cifs_get_inode_info_unix(struct inode **pinode,
                         if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
                                 inode->i_fop->lock = NULL;
                         inode->i_data.a_ops = &cifs_addr_ops;
+                        /* check if server can support readpages */
+                        if(pTcon->ses->server->maxBuf < 
+                            4096 + MAX_CIFS_HDR_SIZE)
+                                inode->i_data.a_ops->readpages = NULL;
                 } else if (S_ISDIR(inode->i_mode)) {
                         cFYI(1, (" Directory inode"));
                         inode->i_op = &cifs_dir_inode_ops;
@@ -384,6 +388,9 @@ int cifs_get_inode_info(struct inode **pinode,
                         if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
                                 inode->i_fop->lock = NULL;
                         inode->i_data.a_ops = &cifs_addr_ops;
+                        if(pTcon->ses->server->maxBuf < 
+                             4096 + MAX_CIFS_HDR_SIZE)
+                                inode->i_data.a_ops->readpages = NULL;
                 } else if (S_ISDIR(inode->i_mode)) {
                         cFYI(1, (" Directory inode "));
                         inode->i_op = &cifs_dir_inode_ops;